Set theme color depending on DevDocs theme

assets/javascripts/app/settings.coffee

@@ -114,16 +114,20 @@ class app.Settings
     @toggleDark(@get('dark') is 1)
     @toggleLayout(layout, @hasLayout(layout)) for layout in @LAYOUTS
     @initSidebarWidth()
+    return
 
   toggleDark: (enable) ->
     classList = document.documentElement.classList
     classList.toggle('_theme-default', !enable)
     classList.toggle('_theme-dark', enable)
+    $('meta[name=theme-color]').setAttribute('content', if enable then '#1c1c1c' else '#eee')
+    return
 
   toggleLayout: (layout, enable) ->
     classList = document.body.classList
     classList.toggle(layout, enable) unless layout is '_sidebar-hidden'
     classList.toggle('_overlay-scrollbars', $.overlayScrollbarsEnabled())
+    return
 
   initSidebarWidth: ->
     size = @get('size')

views/index.erb

@@ -14,6 +14,7 @@
   <meta name="apple-mobile-web-app-capable" content="yes">
   <meta name="apple-mobile-web-app-status-bar-style" content="black">
   <meta name="format-detection" content="telephone=no">
+  <meta name="theme-color" content="#eee">
   <meta name="robots" content="noodp">
   <title>DevDocs API Documentation</title>
   <link rel="canonical" href="<%= canonical_origin %>">

views/other.erb

@@ -5,6 +5,7 @@
   <meta name="viewport" content="width=device-width,initial-scale=1,maximum-scale=1,user-scalable=no">
   <% if doc_index_page? %><meta name="description" content="<%= @doc['name'] %> <%= @doc['release'] %> API documentation with instant search, offline support, keyboard shortcuts, mobile version, and more."><% else %><meta name="robots" content="noindex"><% end %>
   <meta name="format-detection" content="telephone=no">
+  <meta name="theme-color" content="#eee">
   <meta property="og:image" content="<%= App.cdn_origin %>/images/icon-320.png">
   <title>DevDocs<%= " &mdash; #{@doc['full_name']} documentation" if doc_index_page? %></title>
   <link rel="canonical" href="<%= canonical_origin %><%= request.path %>">